nanobots

Nanobots are devices engineered at nanometer scales to perform tasks at the cellular or molecular level. The term is used for both fully autonomous nanoscale machines and nanosized components that require external control. In practice, many demonstrations involve programmable nanomachines built from DNA, peptides, or inorganic materials such as metals and carbon structures. Typical dimensions range from tens to a few hundred nanometers.

Nanobots can be propelled or activated by various energy sources, including chemical reactions, magnetic fields, acoustic waves, or light. Some designs rely on biological motors or enzymatic processes. Control and navigation through complex biological environments remain major challenges, as do issues of biocompatibility, stability, and energy supply.

Applications: In medicine, nanobots are researched for targeted drug delivery, in vivo imaging, and minimally invasive interventions. Other potential uses include environmental sensing and remediation, chemical analysis in situ, and assembly tasks at the nanoscale in materials science. Real-world deployment remains limited to laboratory settings and animal models in most cases.

Current status and challenges: As of the early 2020s, autonomous nanobots that can operate safely inside humans without external guidance have not been realized. Key obstacles include precise control in dynamic environments, scalable manufacturing, safe and rapid clearance from the body, and comprehensive regulatory oversight. Public health and ethical considerations also guide research in this area.

History: The concept of nanoscale machines traces to the ideas of nanotechnology pioneers in the late 20th century, with Feynman's vision of manipulating matter at small scales and Drexler's proposals for molecular machines. Advances in DNA nanotechnology and molecular machinery have provided foundational techniques for constructing nanoscale devices.